Giovanni Sartor

• PhD
• Professor at University of Bologna

With the continued advances in big data analytics and artificial intelligence (AI), it is now possible to rapidly adjust prices of goods and services offered in digital consumer markets. In particular, traders may try to increase their surplus from a purchase based on the availability of a variety of consumers’ data. This may result in different pr...

This paper examines the debate on AI legal personhood, emphasizing the role of path dependencies in shaping current trajectories and prospects. Three primary path dependencies emerge: prevailing legal theories on personhood (singularist vs. clustered), the actual participation of AI in socio-digital institutions (instrumental vs. non-instrumental),...

In this book, expert lawyers from across the full spectrum of EU law explore the impact of the digital age on the Union’s legal framework. The fifth industrial revolution is impacting on all aspects of society. This open access collection looks at how the European Union and its legal framework is reacting, responding, and evolving to best accommoda...

This paper presents an innovative approach to the automated summarization of tax-law decisions developed within the PRODIGIT project. The work addresses the growing challenge of managing large volumes of judicial rulings, which often hinder access to relevant legal precedents. We introduce a hybrid methodology that combines extractive and abstracti...

Despite some improvements in compliance metrics after the implementation of the European General Data Protection Regulation (GDPR), privacy policies have become longer and more ambiguous. They often fail to fully meet GDPR requirements, thus leaving users without a reliable way to understand how their data is processed. We present a novel corpus co...

Causality is vital for establishing legal liability, but traditional analyses often fail to address complex scenarios and conflate causation with legal responsibility. This paper presents a novel approach to cause-in-fact based on argumentation theory which also assesses whether a cause-in-fact lacks legal relevance.

This paper examines the debate on AI legal personhood, emphasizing the role of path dependencies in shaping current trajectories and prospects. Three primary path dependencies emerge: prevailing legal theories on personhood (singularist vs. clustered), the actual participation of AI in socio-digital institutions (instrumental vs. non-instrumental),...

This article continues the research initiated in [1,2], which established a connection between Boolean classifiers and legal case-based reasoning. We relax the assumption that case bases are such that all situations have been decided in favour of the defendant or the plaintiff and we introduce an inductive strategy for assigning plausible outcomes...

Although permissions are of crucial importance in several settings, they have garnered less attention within the deontic logic community than obligations. In previous work we showed how to reconstruct deontic logic using Kelsen’s quasi-causal conception of norms, restricting ourselves to the notion of obligation. Here we extend the account to permi...

Pre-trial detention is a debated measure in different legal systems since it deprives defendants of their liberty prior at the initial stage of proceedings. To order this measure, the judge must justify it by highlighting the risks that the arrested person presents to society and to the criminal procedure itself. An example of a factor related to p...

This paper reconstructs in the context of formal argumentation the notion of stable explanation developed elsewhere in Defeasible Logic. With this done, we discuss the deontic meaning of this notion and show how to build from argumentation neighborhood structures for deontic logic where a stable explanation can be characterised.

Online platforms have become a key infrastructure for creating and sharing content, thus representing a paramount context for the individual/collective exercise of fundamental rights (e.g., freedom of expression, association) and the realisation of social values (citizens’ information, education, democratic dialogue). At the same time, platforms of...

We present some initial results of a large-scale Italian project called PRODIGIT which aims to support tax judges and lawyers through digital technology, focusing on AI. We have focused on generation of summaries of judicial decisions and on the extraction of related information, such as the identification of legal issues and decision-making criter...

This article models legal interpretation through argumentation and provides a logical analysis of interpretive arguments, their conflicts, and the resulting indeterminacies. Interpretive arguments are modelled as defeasible inferences, which can be challenged and defeated by counterarguments and be reinstated through further arguments. It is shown...

This paper examines how a notion of stable explanation developed elsewhere in Defeasible Logic can be expressed in the context of formal argumentation. With this done, we discuss the deontic meaning of this reconstruction and show how to build from argumentation neighborhood structures for deontic logic where this notion of explanation can be chara...

Computational law has its limits—whether these come from the very nature of the law itself or from technical limitations. By reviewing these limits, two conclusions become clear: That interdisciplinary solutions are a must, and that only a subset of law should be turned into automatically processable regulation.

In this paper, we provide a formal framework for modeling the burden of persuasion in legal reasoning. The framework is based on abstract argumentation, a frequently studied method of non-monotonic reasoning, and can be applied to different argumentation semantics; it supports burdens of persuasion with arbitrary many levels, and allows for the pla...

Pretrial detention is a debated and controversial measure since it is an exception to the principle of the presumption of innocence. To determine whether and to what extent legal systems make excessive use of pretrial detention, an empirical analysis of judicial practice is needed. The paper presents some preliminary results of experimental researc...

Preferences are ubiquitous in our everyday life. They are essential in the decision making process of individuals. Recently, they have also been employed to represent ethical principles, normative systems or guidelines. In this work we focus on a ceteris paribus semantics for deontic logic: a state of affairs where a larger set of respected prescri...

This study aims at predicting the outcomes of legal cases based on the textual content of judicial decisions. We present a new corpus of Italian documents, consisting of 226 annotated decisions on Value Added Tax by Regional Tax law commissions. We address the task of predicting whether a request is upheld or rejected in the final decision. We empl...

Creating balanced labeled textual corpora for complex tasks, like legal analysis, is a challenging and expensive process that often requires the collaboration of domain experts. To address this problem, we propose a data augmentation method based on the combination of GloVe word embeddings and the WordNet ontology. We present an example of applicat...

This paper brings together factor-based models of case-based reasoning (CBR) and the logical specification of classifiers. Horty [8] has developed the factor-based models of precedent into a theory of precedential constraint. In this paper we combine binary-input classifier logic (BCL) to classifiers and their explanations given by Liu & Lorini [13...

This paper brings together two lines of research: factor-based models of case-based reasoning (CBR) and the logical specification of classifiers. Logical approaches to classifiers capture the connection between features and outcomes in classifier systems. Factor-based reasoning is a popular approach to reasoning by precedent in AI & Law. Horty (201...

The successful application of argument mining in the legal domain can dramatically impact many disciplines related to law. For this purpose, we present Demosthenes, a novel corpus for argument mining in legal documents, composed of 40 decisions of the Court of Justice of the European Union on matters of fiscal state aid. The annotation specifies th...

In this paper we formalise a meta-argumentation framework as an ASPIC+ extension which enables reasoning about conflicts between formulae of the argumentation language. The result is a standard abstract argumentation framework that can be evaluated via grounded semantics.

The first issue of Artificial Intelligence and Law journal was published in 1992. This paper provides commentaries on nine significant papers drawn from the Journal’s second decade. Four of the papers relate to reasoning with legal cases, introducing contextual considerations, predicting outcomes on the basis of natural language descriptions of the...

A modular extension of Arg-tuProlog, a light-weight argumentation tool, is here presented and discussed, highlighting how it enables reasoning with rules and interpretations of multiple legal systems. Its effectiveness is demonstrated with examples from different national private international law (PIL) laws, running in Arg-tuProlog. PIL addresses...

Targeted advertising in digital markets involves multiple actors collecting, exchanging, and processing personal data for the purpose of capturing users’ attention in online environments. This ecosystem has given rise to considerable adverse effects on individuals and society, resulting from mass surveillance, the manipulation of choices and opinio...

Machine learning classifiers are increasingly used to inform, or even make, decisions significantly affecting human lives. Fairness concerns have spawned a number of contributions aimed at both identifying and addressing unfairness in algorithmic decision-making. This paper critically discusses the adoption of group-parity criteria (e.g., demograph...

Online market players are gradually gaining the capacity to adapt prices dynamically based on knowledge generated through vast amounts of data, so that, theoretically, every individual consumer can be charged the maximum price he or she is willing to pay. This has downsides for markets and society. European Union law insufficiently addresses these...

The volume presents an innovative analysis of defence rights in EU criminal proceedings through the lens of a computational approach to the law. This multi-level research tackles both EU law and national legislation, as well as case-law on defence rights in criminal proceedings. The comparative analysis on procedural safeguards is integrated by leg...

In this paper we present the computational model of Arg2P, a logic-based argumentation framework for defeasible reasoning and agent conversation particularly suitable for explaining agent intelligent behaviours. The model is reified as the Arg2P technology, which is presented and discussed both from an architectural and a technological perspective...

We present a formal semantics for deontic logic based on the concept of ceteris paribus preferences. We introduce notions of unconditional obligation and permission as well as conditional obligation and permission that are interpreted relative to this semantics. We show that these notions satisfy some intuitive properties and, at the same time, do...

This work defines a burden of persuasion meta-argumentation model interpreting the burden as a set of meta-arguments. Bimodal graphs are exploited to define a meta level (dealing with the burden) and an object level (dealing with standard arguments). Finally, an example in the law domain addressing the problem of burden inversion is discussed in de...

Freie, öffentlichen Meinungsbildung ist das Herzstück der Demokratie. Doch digitale Kommunikation und datengetriebene Kuratierung von Inhalten verändern das der Demokratie eigene Konzept von Öffentlichkeit und erfordern neue gesetzliche Rahmenbedingungen. In diesem Sammelband führen Expert:innen der Rechts- und Politikwissenschaften, der Soziologie...

Different formalisms for defeasible reasoning have been used to represent knowledge and reason in the legal field. In this work, we provide an overview of the following logic-based approaches to defeasible reasoning: defeasible logic, Answer Set Programming, ABA+, ASPIC+, and DeLP. We compare features of these approaches under three perspectives: t...

In this paper we provide an analysis of the concept of legal personality and discuss whether personality may be conferred on artificial intelligence systems (AIs). Legal personality will be presented as a doctrinal category that holds together bundles of rights and obligations; as a result, we first frame it as a node of inferential links between f...

We present a logical analysis of influence and control over the actions of others, and address consequential causal and normative responsibilities. We first account for the way in which influence can be exercised over the behaviour of autonomous agents. On this basis we determine the conditions under which influence leads to control on the implemen...

Inspired by Kelsen’s view that norms establish causal-like connections between facts and sanctions, we develop a deontic logic in which a proposition is obligatory iff its complement causes a violation. We provide a logic for normative causality, define non-contextual and contextual notions of illicit and duty, and show that the logic of such dutie...

We present a study aimed at testing the CLAUDETTE system’s ability to generalise the concept of unfairness in consumer contracts across diverse market sectors. The data set includes 142 terms of services grouped in five sub-sets: travel and accommodation, games and entertainment, finance and payments, health and well-being, and the more general oth...

This introduction presents the fifth volume of a series started twelve years ago: the AI Approaches to the Complexity of Legal Systems (AICOL). The introduction revises the recurrently addressed topics of technology, Artificial Intelligence and law and presents new challenges and areas of research, such as the AI ethical and legal turn, hybrid and...

We present the first annotated corpus for multilingual analysis of potentially unfair clauses in online Terms of Service. The data set comprises a total of 100 contracts, obtained from 25 documents annotated in four different languages: English, German, Italian, and Polish. For each contract, potentially unfair clauses for the consumer are annotate...

In this paper we provide an account of the burden of persuasion, in the context of structured argumentation. First, burdens of proof in legal proceedings are discussed in general, distinguishing the burdens of production and the burdens of persuasion. Then, we focus on burdens of persuasion, illustrating their role in civil and criminal law.

In this paper, we provide a formal framework for modeling the burden of persuasion in legal reasoning. The framework is based on abstract argumentation, a frequently studied method of non-monotonic reasoning, and can be applied to different argumentation semantics; it supports burdens of persuasion with arbitrary many levels, and allows for the pla...

This chapter is a light-weighted overview of significant contributions to legal logic insofar as they involve deontic reasoning and related methods. A special emphasis is given to defeasible reasoning, which has been the major topic for legal reasoning in the last decades. The chapter is divided into three parts and the layout is as follows. Part 1...

The study addresses the regulation of targeted and behavioural advertising in the context of digital services. Marketing methods and technologies deployed in behavioural and target advertising are presented. The EU law on consent to the processing of personal data is analysed, in connection with advertising practices. Ways of improving the quality...

In this paper we sketch a vision of explainability of intelligent systems as a logic approach suitable to be injected into and exploited by the system actors once integrated with sub-symbolic techniques.

The principles of transparency and explainability are landmarks of the current EU approach to artificial intelligence. Both are invoked in the policy guidelines as values governing algorithmic decision-making, while providing rationales for existing normative provisions, on information duties, access rights and control powers. This contribution add...

The present contribution aims to address the ways in which legal philosophy approached and conceptualised the emergence of information technologies between the 1960s and 1970s. We will do that by examining the contributions of four thinkers, coming from different philosophical and ideological backgrounds: Vittorio Frosini, Mario Losano, Luigi Lomba...

This book includes revised selected papers from the International Workshops on AI Approaches to the Complexity of Legal Systems, AICOL-XI@JURIX2018, held in Groningen, The Netherlands, on December 12, 2018; AICOL-XII@JURIX 2020, held in Brno, Czechia, on December 9, 2020; XAILA@JURIX 2020, held in in Brno, Czechia, on December 9, 2020.* The 17 full...

We model persuasion, viewed as a deliberate action through which an agent (persuader) changes the beliefs of another agent’s (persuadee). This notion of persuasion paves the way to express the idea of persuasive influence, namely inducing a change in the choices of the persuadee by changing her beliefs. It allows in turns to express different aspec...

The ethics and law of AI address the same domain, namely, the present and future impacts of AI on individuals, society, and the environment. Both are meant to provide normative guidance, proposing rules and values on which basis to govern human action and determine the constrains, structures and functions of AI-enabled socio-technical systems. This...

This work provides a formal model for the burden of persuasion in legal proceedings. The model shows how the allocation of the burden of persuasion may induce a satisfactory outcome in contexts in which the assessment of conflicting arguments would, without such an allocation, remain undecided. The proposed model is based on an argumentation settin...

Private international law (PIL) addresses overlaps and conflicts between legal systems by distributing cases between the authorities of such systems (jurisdiction) and establishing what rules these authorities have to apply to each case(choice of law). A modular argumentation tool, Arg-tuProlog, is here presented that enables reasoning with rules a...

As Autonomous vehicles (AVs) are entering shared roads, the challenge of designing and implementing a completely autonomous vehicle is still open. Aside from technological issues regarding how to manage the complexity of the environment, AVs raise difficult legal issues and ethical dilemmas, especially in unavoidable accident scenarios. In this con...

We present a formal semantics for deontic logic based on the concept of ceteris paribus preferences. We introduce notions of unconditional obligation and permission as well as conditional obligation and permission that are interpreted relative to this semantics. We show that these notions satisfy some intuitive properties and, at the same time, do...

Statutory interpretation involves the reconstruction of the meaning of a legal statement when it cannot be considered as accepted or granted. This phenomenon needs to be considered not only from the legal and linguistic perspective, but also from the argumentative one - which focuses on the strategies for defending a controversial or doubtful viewp...

This paper provides a formal model for the burden of persuasion in dialogues, and in particular, in legal proceedings. The model shows how an allocation of the burden of persuasion may induce single outcomes in dialectical contexts in which, without such an allocation, the status of conflicting arguments would remain undecided. Our approach is base...

What does it mean that something is probably obligatory? And how does it relate to the probability that it is permitted or prohibited? In this paper, we provide a possible answer by merging deontic argumentation and probabilistic argumentation into a probabilistic deontic argumentation framework. This framework allows us to specify a semantics for...

Criminal liability for acts committed by AI systems has recently become a hot legal topic. This paper includes three different contributions. The first contribution is an analysis of the extent to which an AI system can satisfy the requirements for criminal liability: accomplishing an actus reus, having the corresponding mens rea, possessing the co...

Doug Walton, who died in January 2020, was a prolific author whose work in informal logic and argumentation had a profound influence on Artificial Intelligence, including Artificial Intelligence and Law. He was also very interested in interdisciplinary work, and a frequent and generous collaborator. In this paper seven leading researchers in AI and...

In a ceteris-paribus semantics for deontic logic, a state of affairs where a larger set of prescriptions is respected is preferable to a state of affairs where some of them are violated. Conditional preference nets (CP-nets) are a compact formalism to express and analyse ceteris paribus preferences, which nice computational properties. This paper s...

A logical model for arguments dealing with statutory interpretation will be here provided. The basic assumption is that interpretive arguments can be viewed as defeasible inferences: they support their conclusion, but this support is merely presumptive, since it may be challenged by counterarguments. First a general pattern is introduced for repres...

Disputes over causes play a central role in legal argumentation and liability attribution. Legal approaches to causation often struggle to capture cause-in-fact in complex situations, e.g. overdetermination, preemption, omission. In this paper, we first assess three current theories of causation (but-for, NESS, ‘actual causation’) to illustrate the...

Recent years have been tainted by market practices that continuously expose us, as consumers, to new risks and threats. We have become accustomed, and sometimes even resigned, to businesses monitoring our activities, examining our data, and even meddling with our choices. Artificial Intelligence (AI) is often depicted as a weapon in the hands of bu...

We shall first introduce the use of artificial intelligence (AI) in producing new intellectual creations, distinguishing approaches based on knowledge representation and on machine learning. Then we shall provide an overview of some significant applications of AI to the production of intellectual creations, distinguishing the extent to which they d...

Consumer contracts often contain unfair clauses, in apparent violation of the relevant legislation. In this paper we present a new methodology for evaluating such clauses in online Terms of Services. We expand a set of tagged documents (terms of service), with a structured corpus where unfair clauses are liked to a knowledge base of rationales for...

A modular rule-based argumentation system is proposed to represent and reason upon conditional norms featuring obligations, prohibitions, and (strong or weak) permissions. The approach is based on common constructs in computational models of argument: rule-based arguments, argumentation graphs, argument labelling semantics and statement labelling s...

In the court of law, a person can be punished for attempting to commit a crime. An open issue in the study of Artificial Intelligence and Law is whether the law of attempts could be formally modelled. There are distinct legal rules for determining attempted crime whereas the last-act rule (also called proximity rule) represents the strictest approa...

The research aims at a formal definition of constructive interpretation in law as the dynamic of revision of theories about the normative system, embedding a model of balancing values [13] into an architecture of i/o logics representing conceptual, deontological and axiological rules [11]. We also introduce new revision operators which are relevant...

In many legal disputes, determining and evaluating cause-in-fact is a crucial step in the liability attribution. It is, however, difficult and opaque. In this paper, we analyse the cases of overdetermination, where there is more than one cause for the outcome. The proposed framework (FCA) employs logic-based argument modelling. It distinguishes ind...

Terms of service of on-line platforms too often contain clauses that are potentially unfair to the consumer. We present an experimental study where machine learning is employed to automatically detect such potentially unfair clauses. Results show that the proposed system could provide a valuable tool for lawyers and consumers alike.

A bounded-reasoning agent may face two dimensions of uncertainty: firstly, the uncertainty arising from partial information and conflicting reasons, and secondly, the uncertainty arising from the stochastic nature of its actions and the environment. This paper attempts to address both dimensions within a single unified framework, by bringing togeth...

Technology companies have quickly become powerful with their access to large amounts of data and machine learning technologies, but consumers could be empowered too with automated tools to protect their rights.

This paper provides an analysis of how concepts pertinent to legal contracts can influence certain aspects of their digital implementation through smart contracts, as inspired by recent developments in distributed ledger technology. We discuss how properties of imperative and declarative languages including the underlying architectures to support c...

Legal causation is a complex aspect of legal reasoning. Due to its significant role in the attribution of legal responsibility, it is important that there is a clear understanding of the requirements for establishing and reasoning with causal links. This paper presents preliminary results of modelling causal arguments based on the legal decisions w...

We shall first introduce some technical aspects involved in the use of AI in producing new intellectual works, distinguishing approaches based on knowledge representation and on machine learning. Then we shall provide an overview of some of the significant applications of AI to the production of intellectual work, distinguishing the extent to which...

Cambridge Core - Contract Law - European Contract Law in the Digital Age - edited by Stefan Grundmann

AICOL workshops aim to bridge the multiple ways of understanding legal systems and legal reasoning in the field of AI and Law. Moreover, they pay special attention to the complexity of both legal systems and legal studies, on one hand, and the expanding power of the internet and engineering applications, on the other. Along with a fruitful interact...

This contribution explores the consistency in cases having opposite outcomes and different impacts on legally relevant values, both individual rights and social values. The link between outcomes’ impacts on values and factors influencing such impacts is also considered. On this basis a formal analysis of the connection between balancing assessments...